Potentially inappropriate medications and regimen complexity among elderly patients in the emergency department: Insights from a pharmacist-led medication reconciliation study

Background: Polypharmacy and potentially inappropriate medications (PIMs) exposure are common in older adults, especially in emergency departments (EDs) with rapid decisions and incomplete histories. Pharmacist-led medication reconciliation improves safety but is rarely implemented in Iran. Objective: This study aimed to evaluate the prevalence and patterns of PIM use, medication regimen complexity, and associated factors among elderly patients admitted to the ED. Methodology: This cross-sectional study of patients aged 65+ years at Alzahra Hospital (October 2023-March 2024) involved medication reconciliation by pharmacy students under supervision. PIMs were identified using the 2023 American Geriatrics Society (AGS) Beers Criteria. Medication complexity and comorbidities were assessed via Medication Regimen Complexity Index (MRCI) and Charlson Comorbidity Index (CCI), with results analyzed through regression. Results: A total of 200 patients were included (mean age 78.1 ± 7.8 years; males: 109, 54.5%). Polypharmacy was observed in 104 patients (52%). The mean MRCI was 23.8 ± 13.5, and the mean CCI was 2.3 ± 1.6. PIM exposure was identified in 75 patients (37.5%), with 221 PIM prescriptions. The most frequent PIM classes were benzodiazepines (49/221, 22.2%), atypical antipsychotics (28/221, 12.7%), opioids (24/221, 10.9%), and Non-Steroidal Anti-Inflammatory Drugs (NSAIDs: 18/221, 8.1%). Clinically significant drug-drug interactions occurred in 30 patients (15%). Female sex, mild comorbidity (CCI, 1-2), and higher MRCI independently predicted PIM use. Conclusions: PIM exposure was frequent among elderly ED patients. Pharmacist-led medication reconciliation effectively identified inappropriate prescribing and complex regimens, supporting the integration of clinical pharmacists into emergency care to improve geriatric medication safety.